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1.
J Colloid Interface Sci ; 636: 291-304, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36638569

RESUMO

The application of photothermal materials in seawater desalination, wastewater treatment have been widely studied, however, there are relatively few studies that combine photothermal effects and solar-driven photocatalysis and exhibit efficient solar-driven water evaporation performance and excellent photocatalytic ability. Form the perspective of practical application, it is of great significance to combine photothermal effect with solar-driven photocatalysis to develop environment-friendly evaporator with low cost, simple preparation process and ability of seawater desalination, wastewater treatment and photodegradation of organic dyes. In this paper, a novel multifunctional MXene/polypyrrole (PPy) coated melamine foam (MF) named as MF-MXene/PPy was successfully prepared by simple impregnation and in-situ polymerization. The MF-MXene/PPy has rich porosity (89.13 %), abundant water molecule transport channels, excellent light absorption capacity (about 94 %), low thermal conductivity (0.1047 W m-1 K-1), and exhibits excellent performance in solar desalination, wastewater purification and photodegradation of organic dyes. Under 1 kW m-2 illuminate, the solar energy conversion rate and efficiency of MF-MXene/PPy reaches up to 1.5174 kg m-2h-1 and 91.24 %. Moreover, due to the regular pore size of MF-MXene/PPy, good salinity tolerance was shown even after continuous evaporation in 20 wt% NaCl for 8 h. After continuous evaporation in 70 mL of 20 wt% NaCl for 8 h, the amount of salt collected could reach 0.2 g. In addition, MF-MXene/PPy also possessed excellent visible light degradation ability for organic dyes, and the degradation rate of methylene blue (MB), rhodamine B (RHB) and methyl orange (MO) were 92.38 %, 88.92 % and 91.75 %, respectively. As a fundamental research, this research will open a novel way to the development of new evaporator.

2.
Anal Methods ; 13(39): 4538-4556, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34570126

RESUMO

Molecular imprinting technology for the preparation of polymers with specific molecular recognition function had become one of the current research hotspots. It has been widely applied in chromatographic separation, antibody and receptor mimetics, solid-phase extraction, bio-sensors, and other fields in the last decades. In this study, molecular imprinting technology was summarized from the points of templates and dummy templates, and four typical target analytes were selected to compare the differences between templates and dummy templates. The current status and prospects of molecular imprinting technology were also proposed.


Assuntos
Impressão Molecular , Polímeros , Extração em Fase Sólida
3.
Curr Top Med Chem ; 20(27): 2427-2441, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32842941

RESUMO

Nanotechnology has revolutionized cancer treatment in both diagnosis and therapy. Since the initial application of nanoparticles (NPs) in cancer treatment, the main objective of nanotechnology was developing effective nanosystems with high selectivity and specificity for cancer treatment and diagnosis. To achieve this, different encapsulation and conjugation strategies along with surface functionalization techniques have been developed to synthesize anticancer drugs loaded NPs with effective targeting to specific tumor cells. The unique physicochemical attributes of NPs make them promising candidates for targeted drug delivery, localized therapies, sensing, and targeting at cellular levels. However, a nanosystem for localized and targeted cancer managements should overcome several biological barriers and biomedical challenges such as endothelial barriers, blood brain barrier, reticuloendothelial system, selective targeting, biocompatibility, acute/chronic toxicity, tumor-targeting efficacy. The NPs for in vivo applications encounter barriers at system, organ, and the cellular level. To overcome these barriers, different strategies during the synthesis and functionalization of NPs should be adapted. Pharmacokinetics and cellular uptake of NPs are largely associated with physicochemical attributes of NPs, morphology, hydrodynamic size, charge, and other surface properties. These properties can be adjusted during different phases of synthesis and functionalization of the NPs. This study reviews the advances in targeted cancer treatment and the parameters influencing the efficacies of NPs as therapeutics. Different strategies for overcoming the biological barriers at cellular, organ and system levels and biomedical challenges are discussed. Moreover, the applications of NPs in preclinical and clinical practice are reviewed.


Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Nanopartículas/química , Neoplasias/tratamento farmacológico , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Humanos , Nanotecnologia , Neoplasias/patologia
4.
JPEN J Parenter Enteral Nutr ; 44(7): 1308-1317, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31769063

RESUMO

BACKGROUND: Radiation-induced gastrointestinal syndrome, including nausea, diarrhea, and dehydration, contributes to morbidity and mortality after medical or industrial radiation exposure, which seriously affects patient quality of life after treatment. No safe and effective radiation countermeasure has been approved for clinical therapy. In this study, we aimed to investigate the potential protective effects of phycocyanin (PC) against radiation-induced acute intestinal injury. MATERIALS AND METHODS: C57BL/6 mice were orally administered 50 mg/kg PC once per day for 1 month before exposure to total-abdominal x-ray irradiation at a single dose of 12 Gy. The effects of PC on intestinal histopathology and integrity, gut microbiota, lipopolysaccharides (LPS), inflammatory cytokines, and Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (Myd88)/nuclear factor κB (NF-κB) signaling were evaluated. RESULTS: Severe histopathological damage, such as intestinal mucosal epithelial cell apoptosis, necrosis, and nuclear rupture, was most clearly observed 24 hours after total-abdominal x-ray irradiation. Intestinal integrity was damaged by irradiation, which manifested in reduced levels of the tight-junction proteins Claudin-1, Occludin, and zonula occludens-1(ZO-1). PC pretreatment significantly ameliorated radiation-induced intestinal injury. PC also modulated the gut microbiota composition, increasing the proportion of beneficial bacteria and decreasing that of harmful bacteria, which in turn lowered LPS levels and suppressed TLR4/Myd88/NF-κB pathway activation. Finally, levels of corresponding inflammatory cytokines, including tumor necrosis factor α and interleukin-6, were also downregulated. CONCLUSION: PC protects against mouse intestinal injury from high-dose radiation by regulating the effect of the gut microbiota on the TLR4/Myd88/NF-κB pathway, suggesting PC as a promising natural radiation countermeasure.


Assuntos
Microbioma Gastrointestinal , Receptor 4 Toll-Like , Animais , Humanos , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos C57BL , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Ficocianina/farmacologia , Qualidade de Vida , Receptor 4 Toll-Like/metabolismo
5.
Pak J Pharm Sci ; 32(5(Special)): 2459-2464, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31894035

RESUMO

The study aimed to develop a HPLC method for ephedrine, hesperidin, and baicalin in Lung-Ventilating-Regulating Oral Liquid. The three active constituents were identified in an Agilent TC-C18 (2) chromatographic column (250mm × 4.6mm, 5µm), with 0.2% phosphoric acid solution - methyl cyanides as mobile phase, which was performed at a gradient elution column temperature of 25oC and a flow rate of 0.8 mL•min-1. Then the eluate was detected at detection wavelengths of 207 nm (for ephedrine) and 278 nm (for hesperidin and baicalin). Under the chromatographic conditions, ephedrine, hesperidin, and baicalin were well separated, which showed good linear relationships at 0.158-2.370, 0.164-4.100 and 0.160-4.000µg, respectively. The coefficients of recovery of these three kinds of samples showed 100.2%, 98.7% and 97.8%, respectively. The developed method is convenient, accurate and well repeatable, and consequently can be applied for the quality control of Lung-Ventilating-Regulating Oral Liquid.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Efedrina/química , Flavonoides/química , Hesperidina/química
6.
Macromol Biosci ; 18(11): e1800234, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30259651

RESUMO

Chemokine receptor CXC receptor 4 (CXCR4) plays a crucial role in cell invasion and metastasis of multiple types of cancer. Dual-function polymeric CXCR4 antagonists based on cyclam-modified poly(ethylenimine) (C-PEI) have been shown to have potential as nucleic acid delivery vectors and antimetastatic therapeutics in recent studies. How cholesterol modification of C-PEI affects the ability of the polycation to deliver siRNA and inhibit CXCR4 is tested here. It is shown that the C-PEI with the lower content of cholesterol exhibits the highest siRNA transfection efficiency and demonstrates enhanced CXCR4 antagonism and antimetastatic activity in a breast cancer model in vivo. Overall, the cholesterol modification of C-PEI is a viable strategy to achieve efficient delivery of siRNA and simultaneous CXCR4 inhibition for combined antimetastatic therapies is validated by this study.


Assuntos
Portadores de Fármacos , Neoplasias Mamárias Experimentais/tratamento farmacológico , Proteínas de Neoplasias/antagonistas & inibidores , Polietilenoimina , RNA Interferente Pequeno , Receptores CXCR4/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Feminino , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Polietilenoimina/química , Polietilenoimina/farmacologia , RNA Interferente Pequeno/química , RNA Interferente Pequeno/farmacologia , Receptores CXCR4/genética , Receptores CXCR4/metabolismo
7.
ScientificWorldJournal ; 2013: 848201, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24078797

RESUMO

In the Junggar basin, northwest China, many high gamma-ray (GR) sandstone reservoirs are found and routinely interpreted as mudstone non-reservoirs, with negative implications for the exploration and exploitation of oil and gas. Then, the high GR sandstone reservoirs' recognition principles, genesis, and log evaluation techniques are systematically studied. Studies show that the sandstone reservoirs with apparent shale content greater than 50% and GR value higher than 110API can be regarded as high GR sandstone reservoir. The high GR sandstone reservoir is mainly and directly caused by abnormally high uranium enrichment, but not the tuff, feldspar or clay mineral. Affected by formation's high water sensitivity and poor borehole quality, the conventional logs can not recognize reservoir and evaluate the physical property of reservoirs. Then, the nuclear magnetic resonance (NMR) logs is proposed and proved to be useful in reservoir recognition and physical property evaluation.


Assuntos
Raios gama , Silicatos de Alumínio , China , Argila , Geologia , Espectroscopia de Ressonância Magnética , Campos de Petróleo e Gás/química , Compostos de Potássio , Monitoramento de Radiação , Urânio/química
8.
Se Pu ; 24(3): 294-7, 2006 May.
Artigo em Chinês | MEDLINE | ID: mdl-16929852

RESUMO

A microemulsion electrokinetic chromatography (MEEKC) method for the determination of andrographolide and dehydroandrographolide in Xiaoyanlidan Tablets was established. The MEEKC method involved the use of sodium dodecyl sulfate (SDS) as surfactant, ethyl acetate as organic solvent and 1-butanol as co-surfactant. The effects of several factors such as the acidity and concentration of borate buffer, SDS and 1-butanol contents were investigated. The optimized composition (by mass) of microemulsion system are 0.5% ethyl acetate--0.6% SDS--6.0% 1-butanol--92.9% 30 mmol/L sodium tetraborate buffer (pH 9.5). This system allowed a useful and reproducible separation of the analytes to be achieved in less than 6 min. The proposed method is a simple, fast and sensitive method for the determination of andrographolide and dehydroandrographolide in Xiaoyanlidan Tablets.


Assuntos
Diterpenos/análise , Medicamentos de Ervas Chinesas/química , Medicina Tradicional Chinesa , Extratos Vegetais/química , Comprimidos/química
9.
J Sep Sci ; 29(1): 164-71, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16485722

RESUMO

Novel HPLC methods were developed for the analytical and semipreparative resolution of new antianginal drug ranolazine enantiomers. Good baseline enantioseparation was achieved using cellulose tris (3,5-dimethylphenylcarbamate) (CDMPC) chiral stationary phases (CSPs) under both normal-phase and polar organic modes. The validation of the analytical methods including linearity, LODs, recovery, and precision, and the semipreparative resolution of ranolazine racemate were carried out using methanol as mobile phase without any basic and acidic additives under polar organic mode, using CDMPC CSPs. At analytical scale, the elution times of both enantiomers were less than 7.5 min at 20 degrees C and 1.0 mL/min, with the separation factor (a) 1.88 and the resolution factor (R(s)) 2.95. At semipreparative scale, about 14.3 mg/h enantiomers could be isolated and elution times of both enantiomers were less than 13 min at 2.0 mL/min. To increase the throughput, the technique of overlapping injections was used. The first eluted enantiomer was isolated with a purity of 99.6% enantiomer excess (e.e.) and > 99.0% yield. The second enantiomer was isolated with a purity of 98.8% e.e. and > 99.0% yield. In addition, optical rotation and circular dichroism spectroscopy of both ranolazine enantiomers isolated were also investigated.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Piperazinas/isolamento & purificação , Polissacarídeos/química , Acetanilidas , Calibragem , Estrutura Molecular , Piperazinas/química , Ranolazina , Reprodutibilidade dos Testes , Estereoisomerismo
10.
Anal Bioanal Chem ; 384(4): 939-45, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16402177

RESUMO

HPLC methods have been developed for chiral resolution of the enantiomers of dl-tetrahydropalmatine (THP) and dl-tetrahydroberberine (THB), two active constituents of Corydalis yanhusuo W.T. Wang. On the analytical scale, good baseline separation of the enantiomers was achieved using cellulose tris(3,5-dimethylphenylcarbamate) chiral stationary phases in both normal-phase and polar organic modes. Validation of the analytical methods, including linearity, limits of detection, recovery, and precision, and semipreparative resolution of dl-THP and dl-THB, were achieved with methanol as mobile phase, without any basic additives, in polar organic mode using cellulose tris(3,5-dimethylphenylcarbamate) chiral stationary phases. On the semipreparative scale, small quantities of the individual enantiomers of THP and THB were isolated for study of the chiroptical properties of the individual enantiomers.


Assuntos
Alcaloides de Berberina/análise , Berberina/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Corydalis/química , Berberina/análise , Análise Espectral/métodos , Estereoisomerismo
11.
J Pharm Biomed Anal ; 41(1): 124-8, 2006 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-16318907

RESUMO

A rapid cyclodextrin modified micellar electrokinetic chromatography (CD-MEKC) method was proposed for the determination of resibufogenin and cinobufagin in the Chinese herbal extracts from toad venom and its medicinal preparation (Liushen tablet). The two components have the close structural similarity and similar hydrophobicity, which result in poor resolution in normal MEKC. The addition of neutral beta-CD to the MEKC system was found to improve the separation of the studied compounds. The effects of several CD-MEKC parameters on the resolutions were evaluated systematically. Based on the investigation, a background electrolyte solution consisting of 10 mM borate buffer adjusted to pH 8.5, 40 mM sodium dodecyl sulfate (SDS), 12 mM beta-CD and 10% (v/v) of methanol was found to be optimal conditions for the fast separation. The contents of resibufogenin and cinobufagin were successfully determined within 5 min, with satisfactory repeatability and recovery.


Assuntos
Venenos de Anfíbios/análise , Bufanolídeos/análise , Química Farmacêutica/métodos , Cromatografia/métodos , Eletroquímica/métodos , Comprimidos/análise , Tecnologia Farmacêutica/métodos , beta-Ciclodextrinas/análise , Animais , Concentração de Íons de Hidrogênio , Medicina Tradicional Chinesa , Metanol/química , Modelos Químicos , Ranidae , beta-Ciclodextrinas/química
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